Combined acute effects of red wine consumption and cigarette smoking on haemodynamics of young smokers

OBJECTIVE

Red wine seems to improve haemodynamic variables, while smoking provokes adverse effects. The haemodynamic effects of their combined use is unknown. The purpose of the present study was to examine the acute effects of red wine and its constituents, in combination with the smoking of one cigarette, on haemodynamic parameters, such as blood pressure and wave reflections, in a group of smokers.

METHODS

Twenty smokers (12 males, eight females) participated in a double-blind, crossover study comprised of 3 study days. All subjects either smoked one cigarette, or smoked and drank 250 ml of red wine, or 250 ml of de-alcoholized red wine (containing the same type and similar concentration of antioxidants). Applanation tonometry and generalized transfer functions were used to estimate aortic pressure waveforms at baseline and 30, 60 and 90 min after each trial. The augmentation index (AIx) was used to express wave reflections.

RESULTS

Smoking increased peripheral systolic blood pressure (P < 0.005) 30 min later, but simultaneous consumption of either type of red wine caused no such effect. Additionally, smoking caused no overall effect on AIx, while smoking and drinking either regular or de-alcoholized red wine reduced AIx (P < 0.001). The reduction of AIx after red wine consumption was significantly greater than the respective reduction after de-alcoholized red wine (P = 0.004).

CONCLUSION

Antioxidant substances in red wine counteracted the smoking-induced increase in peripheral systolic blood pressure. Both alcohol and antioxidants in red wine decrease wave reflections in uncomplicated habitual smokers postprandially, indicating an additional favourable effect of red wine.

Cerebral Hemodynamics in Preeclampsia: Cerebral Perfusion and the Rationale for an Alternative to Magnesium Sulfate

Preeclampsia and eclampsia continue to be major causes of maternal death. Currently, approximately 18% of U.S. maternal deaths are attributed to hypertensive disorders and eclampsia, and several hundred women die from eclampsia and its complications every year. In the United States, preeclamptic women have received magnesium sulfate as a seizure prophylaxis agent for 3 decades, and this practice is becoming more widely accepted internationally. In addition to a recognized failure rate, there are financial, logistic, and safety concerns associated with the universal administration of magnesium sulfate. Many institutions in the developing world lack the necessary equipment and expertise to administer the medication, and many preeclamptic patients thus do not receive magnesium sulfate before their first seizure. As effective as it has been in reducing mortality from eclampsia, magnesium sulfate is also associated with appreciable morbidity and mortality from administration errors and magnesium toxicity. The availability of an easily administered, cheap, safe, and orally administered alternative to magnesium sulfate would be welcomed in the developing world and would provide an extremely useful alternative therapy to the current standard of care. Recent advances in the understanding of the pathophysiology of preeclampsia and eclampsia, primarily related to cerebral perfusion and blood flow, could allow us to reduce the seizure rate in treated preeclamptic women even further than what is currently reported. This article deals with the rationale behind the use of labetalol as an alternative to magnesium sulfate for the prevention of eclampsia.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to recall that hypertensive diseases of pregnancy contribute a significant portion of today's maternal mortality, explain that methods of preventing eclampsia are not applicable worldwide, and state that understanding of the pathophysiology of preeclampsia/eclampsia may assist in developing safe and effective medications that can be used universally.

A randomized comparative study of the effects of oral and topical estrogen therapy on the vaginal vascularization and sexual function in hysterectomized postmenopausal women

OBJECTIVE

To compare the effects of oral and vaginal estrogen therapy (ET) on the vaginal blood flow and sexual function in postmenopausal women with previous hysterectomy.

DESIGN

Fifty-seven women were randomized to receive either oral (0.625 mg of conjugated equine estrogens per tablet; n = 27) or topical (0.625 mg conjugated equine estrogens per 1 g vaginal cream; n = 30) estrogen administered once daily. All women underwent estradiol measurements, urinalysis, pelvic examination, introital color Doppler ultrasonographies, and personal interviews for sexual symptoms using a validated questionnaire before and 3 months after ET.

RESULTS

A higher serum level of estradiol was noted in the oral group compared with the topical group after 3 months of ET. There were significant increases in the number of vaginal vessels and the minimum diastole (P < 0.01), and marked decreases of pulsatility index values (P < 0.01) in both groups after ET. Regarding the systolic peak, we found a significant decrease only in the topical group (P < 0.05). Although the post-ET prevalence of anorgasmia decreased significantly in both groups (P < 0.05), changes in other domains, including the rates of low libido and coital frequency, were not statistically significant (P > 0.05). In the topical group, ET improved sexual function on the vaginal dryness and dyspareunia domains in a statistically significant manner (P < 0.05), but this was not the case in the oral group (P > 0.05). However, the efficacy of oral ET for vaginal dryness and dyspareunia reached 80% and 70.6%, respectively. The corresponding figures of the topical ET were 79.2% and 75%.

CONCLUSIONS

The results of our study suggest that ET alone in hysterectomized postmenopausal women increases the vaginal blood flow and improves some domains of sexual function, but it may not have an impact on diminished sexual desire or activity. Compared with systemic therapy, topical vaginal preparations are found to correlate with better symptom relief despite the lower serum level of estradiol.

Treatment of growth hormone excess in dogs with the progesterone receptor antagonist aglépristone

Acromegaly or hypersomatotropism in dogs is almost always due to progestin-induced hypersecretion of GH originating from the mammary gland. The aim of this study was to investigate whether aglépristone, a progesterone receptor antagonist, can be used to treat this form of canine acromegaly. In five Beagle bitches hypersomatotropism was induced by administration of MPA for over 1 year. Subsequently, aglépristone was administered. Blood samples were collected before MPA administration, immediately before, during, and 3.5 and 5.5 weeks after the last administration of aglépristone for determination of the plasma concentrations of GH and IGF-I. In addition, blood samples for the determination of the 6-h plasma profile of GH were collected before MPA administration, before aglépristone administration, and 1 week after the last aglépristone treatment. MPA administration resulted in a significant increase of the mean plasma IGF-I concentration, whereas analysis of the pulsatile plasma profile demonstrated a trend (P=0.06) for a higher mean basal plasma GH concentration and a higher mean AUC(0) for GH. Treatment with aglépristone resulted in a significant decrease of the mean plasma GH and IGF-I concentrations. Analysis of the pulsatile plasma profile showed a trend (P=0.06) for a lower mean basal plasma GH concentration and a lower mean AUC(0) for GH 1 week after the last aglépristone treatment compared with these values before aglépristone administration. Three and a half and 5.5 weeks after the last aglépristone administration the mean plasma IGF-I concentration increased again. In conclusion, aglépristone can be used successfully to treat dogs with progestin-induced hypersomatotropism.

Effects of Oral L-Arginine on the Foetal Condition and Neonatal Outcome in Preeclampsia: A Preliminary Report

Estimation of the influence of oral supplementation with low dose of L-arginine on biophysical profile, foeto-placental circulation and neonatal outcome in preeclampsia. Randomized, placebo-controlled, double-blind, clinical trial. Oral therapy with 3 g of L-arginine daily or placebo as a supplement to standard therapy. Eighty-three preeclamptic women, randomly assigned to the L-arginine (n=42) or placebo (n=41) groups; [n=30 (L-arginine) and n=31 (placebo) ended the study, respectively]. Foetal gain chances due to ultrasound biometry, biophysical profile, Doppler velocimetry of pulsatility indices of umbilical and middle cerebral arteries, cerebro-placental ratio, as well as differences in duration of pregnancy and clinical data of newborn. L-arginine treatment transitory accelerated foetal gain and improved biophysical profile. Starting from 3rd week of therapy, the umbilical artery pulsatility indices values were significantly lower in L-arginine than in placebo group. Moreover, treatment with L-arginine caused significant increase of middle cerebral artery pulsatility indices and cerebro-placental ratio values. Latency was longer in L-arginine group. Neonates delivered in the L-arginine group revealed higher Apgar score. Supplementary treatment with oral L-arginine seems to be promising in improving foetal well-being and neonatal outcome as well as in prolonging pregnancy complicated with preeclampsia. However, these benefits require confirmation in more-powered, larger studies.

Aging and vascular responses to flavanol-rich cocoa

OBJECTIVES

Strong evidence has secured aging as a powerful predictor of both cardiovascular risk and endothelial dysfunction, yet specific treatment is not available. We tested the hypothesis that vascular responsiveness to flavanol-rich cocoa increases with advancing age. We have previously shown that flavanol-rich cocoa induced peripheral vasodilation, improving endothelial function via a nitric oxide (NO)-dependent mechanism.

METHODS

We studied blood pressure and peripheral arterial responses to several days of cocoa in 15 young (< 50 years) and 19 older (> 50) healthy subjects.

RESULTS

The nitric oxide synthase (NOS) inhibitor N(omega)-nitro-L-arginine-methyl-ester (L-NAME) induced significant pressor responses following cocoa administration only among the older subjects: systolic blood pressure (SBP) rose 13 +/- 4 mmHg, diastolic blood pressure (DBP) 6 +/- 2 mmHg (P = 0.008 and 0.047, respectively); SBP was significantly higher in the older subjects (P < 0.05). Flow-mediated vasodilation, measured by tonometry in the finger, was enhanced with flavanol-rich cocoa in both groups, but significantly more so among the old (P = 0.01). Finally, basal pulse wave amplitude (PWA) followed a similar pattern. Four to six days of flavanol-rich cocoa caused a rise in PWA in both groups. At peak vasodilation following acute cocoa intake on the final day, both groups showed a further, significant rise in PWA. The response in the older subjects was more robust; P < 0.05. L-NAME significantly reversed dilation in both groups.

CONCLUSIONS

Flavanol-rich cocoa enhanced several measures of endothelial function to a greater degree among older than younger healthy subjects. Our data suggest that the NO-dependent vascular effects of flavanol-rich cocoa may be greater among older people, in whom endothelial function is more disturbed.

Effect of methionine loading on pulse wave analysis in elderly volunteers

OBJECTIVE

To test the hypothesis that an acute increase in plasma homocysteine produced by methionine is associated with an acute increase in pulse wave velocity.

DESIGN

A double blind, cross over, placebo controlled design was used and pulse wave velocity, plasma homocysteine, total cholesterol: high density lipoprotein ratio, plasma triglyceride, oxidised low density lipoprotein cholesterol concentrations, apolipoproteins A1 and B, and C reactive protein were measured between 12.5 and 20 hours after methionine loading or placebo.

RESULTS

Between 12.5 and 20 hours after exposure to a methionine loading test, arterial pulse wave velocity showed no significant difference compared with placebo. At 12 hours after exposure to the methionine loading test, in the presence of a controlled diet, triglyceride concentration significantly increased by 32.6% (p<0.02), cholesterol: high density lipoprotein ratio increased significantly by 22.5% (p<0.05) compared with placebo. Simultaneously, systolic blood pressure increased significantly by 4.9% (p<0.02).

CONCLUSION

In elderly volunteers, acute hyperhomocysteinaemia induced by methionine loading resulted in no overall significant delayed reduction in peripheral arterial distensibility. A significant deterioration in the lipid profile and increased blood pressure was seen during acute hyperhomocysteinaemia.

Effect of sildenafil on arterial stiffness, as assessed by pulse wave velocity, in patients with erectile dysfunction

BACKGROUND

The problems of patients with erectile dysfunction have been recognized, leading to the emergence of sildenafil, which has led to successful treatment in many cases. The purpose of this study is to examine the effect of sildenafil on the pulse wave velocity of patients with erectile dysfunction.

METHODS

Fifteen patients with erectile dysfunction were enrolled for this study. The brachial/ankle pulse wave velocity was determined before dosing and at 30, 60, 120, and 180 min after dosing with 25 or 50 mg of sildenafil citrate. Concurrently, the changes in blood pressure, heart rate, and brachial/ankle pulse wave velocity were measured. For the consideration of revised brachial/ankle pulse wave velocity by blood pressure, the systolic blood pressure-derived brachial/ankle pulse wave was also investigated, and we classified and examined those results with and without risk factors for arteriosclerosis.

RESULTS

The systolic blood pressure decreased significantly at 60 min after dosing compared with the placebo control. The heart rate decreased at 120 min after dosing compared with the placebo control but that decrease was not significant. The brachial/ankle pulse wave velocity transiently decreased at 30 or 60 min after dosing compared with the placebo control, but the decrease was not significant; however, the systolic blood pressure-derived brachial/ankle pulse wave velocity decreased significantly. In those patients with risk factors for arteriosclerosis, the pulse wave velocity decreased significantly.

CONCLUSION

In patients with erectile dysfunction who were administered sildenafil, the pulse wave velocity, along with blood pressure, tended to decrease transiently after dosing. There is a possibility that sildenafil affects the improvement of erectile dysfunction via the decrease of pulse wave velocity, especially in patients with risk factors for arteriosclerosis.

Systolic and diastolic hypertension impair endothelial vasodilatory function in different types of vessels in the elderly: the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study

BACKGROUND

Endothelium-dependent vasodilation (EDV) is known to be impaired in middle-aged hypertensive individuals, but less is known regarding hypertension in the elderly.

OBJECTIVE

In the Prospective Study of the Vasculature in Uppsala Seniors (PIVUS) study, different techniques to evaluate EDV in resistance and conduit arteries were applied in elderly subjects and were related to the type of hypertension.

DESIGN AND METHODS

In this population-based study, 1016 subjects aged 70 years were evaluated by the invasive forearm technique with acetylcholine (EDV), brachial artery ultrasound to assess flow-mediated dilatation (FMD) and pulse wave analysis with a beta-2 receptor agonist challenge, terbutaline. Those without antihypertensive treatment were divided into three groups: normotensive individuals (n = 256), and those with isolated systolic hypertension (n = 309) or combined systolic/diastolic hypertension (n = 79).

RESULTS

Compared with normotensive individuals, EDV was reduced in those with combined systolic/diastolic hypertension only (P = 0.0019), whereas FMD was mainly reduced in those with isolated systolic hypertension (P = 0.013). Furthermore, in regression analysis, EDV was related to diastolic blood pressure only (r = -0.10, P = 0.017), whereas FMD was mainly related to systolic blood pressure (r = -0.13, P = 0.0023). The pulse wave-based method to analyse vasoreactivity was not consistently affected by hypertension.

CONCLUSIONS

In elderly subjects, systolic hypertension mainly impairs conduit artery endothelial vasodilatory function, whereas diastolic hypertension mainly induces dysfunction in resistance arteries.

Influence of nebivolol and enalapril on metabolic parameters and arterial stiffness in hypertensive type 2 diabetic patients

OBJECTIVE

To compare the effects of a cardioselective beta-blocker (nebivolol) with those of an angiotensin-converting enzyme inhibitor (enalapril) on parameters of insulin sensitivity, peripheral blood flow and arterial stiffness during one extended glucose clamp experiment.

DESIGN

A randomized, double-blind crossover trial, consisting of two 12-week treatment phases separated by a 4-week wash-out phase.

METHODS

Patients with type 2 diabetes and arterial hypertension were randomly assigned to one of two treatment sequences (nebivolol-enalapril, enalapril-nebivolol). Haemodynamic, metabolic and other laboratory measurements were carried out on the first and last day of each treatment period by means of a glucose clamp experiment that also involved the measurement of blood flow and arterial stiffness.

RESULTS

Twelve patients were included in this study, of which two dropped out early. Efficacy parameters were therefore available for 10 patients. There was no significant difference in any of the primary efficacy parameters. Moreover, the effects on blood pressure did not significantly differ between both treatments. Six adverse events happened during treatment with nebivolol compared with two during treatment with enalapril, but only one was regarded as possibly related to the treatment.

CONCLUSIONS

This pilot study shows that the combined measurement of insulin sensitivity, blood flow and arterial stiffness is feasible. Nebivolol and enalapril did not show different effects with regard to these parameters in hypertensive diabetic patients. If these results are confirmed in larger clinical trials, this would argue against the reservations against beta-blockers as drugs of first choice in patients with diabetes because of potential metabolic side-effects.

Acute Effect of Black and Green Tea on Aortic Stiffness and Wave Reflections

OBJECTIVE

While most studies have shown an inverse relation between tea consumption and cardiovascular risk, other studies have shown opposite results. Aortic stiffness and wave reflections are markers of cardiovascular disease and prognosticators of cardiovascular risk.

METHODS

The acute effect of black and green tea on aortic stiffness and wave reflections was assessed in 29 healthy volunteers in a randomized, single-blind, sham-procedure controlled, cross-over design. In the black tea sub-study, 16 subjects received 6 gm of tea, caffeine (175 mg), or hot water in 3 different sessions. In the green tea sub-study, 13 subjects received 6 gm of tea, caffeine (125 mg), or hot water. Carotid-femoral pulse wave velocity and wave reflection indices were measured at baseline and for 3 hours after consumption.

RESULTS

Black tea increased pulse wave velocity during the first 90 min (increase by 0.49 m/sec, P < 0.05), showing a rapid return towards baseline values thereafter (P = 0.07 for the whole study period); in contrast, green tea had no effect. Both black and green tea increased augmentation index (by 5.0% and by 6.6%, P < 0.01 and P < 0.001, respectively) throughout the study. These changes were less than the respective changes produced by caffeine. Both black and green tea had a significant pressor effect. No change in oxidant status was found with both types of tea.

CONCLUSIONS

Both black and green tea increases acutely wave reflections and only black tea increases aortic stiffness. Tea flavonoids may play a role in the attenuation of the effects of caffeine contained in tea.

Effects of iodinated contrast media on common carotid and brachial artery blood flow and wall shear stress

The aim of our study was to evaluate the effect of the intravenous contrast media iomeprol on wall shear stress, blood flow and vascular parameters in the common carotid and brachial artery. Thirty outpatients undergoing thoracic or abdominal spiral CT scans were studied. The internal diameter and flow velocity of the common carotid and brachial artery were evaluated by ultrasound, and blood viscosity was measured before and after low osmolality iomeprol (Iomeron 350) injection. The wall shear stress, blood flow and pulsatility index were calculated. To test the differences between groups, the Wilcoxon rank test and Mann Whitney U test were applied. Blood viscosity decreased slightly, but significantly after contrast media (4.6+/-0.7 vs. 4.5+/-0.7 mPa.s, P = 0.02). Contrarily, blood flow and wall shear stress did not change in the common carotid artery, but significantly decreased in the brachial artery (0.9+/-0.4 vs. 0.6+/-0.3 ml/s, P < 0.0001, and 41.5+/-13.9 vs. 35.3+/-11.0 dynes/cm2, P < 0.002, respectively), whereas the pulsatility index significantly increased in the brachial artery (5.0+/-3.3 vs. 7.5+/-5.3, P < 0.001). Iomeprol injection causes blood flow and wall shear stress reduction of the brachial artery; the rise in the pulsatility index suggests an increase in peripheral vascular resistance. Further investigation is needed to evaluate whether these modifications can be clinically relevant.

Role of nitric oxide in the regulation of digital pulse volume amplitude in humans

Measurement of the increase in digital pulse volume amplitude (PVA) during reactive hyperemia relative to baseline (PVA-RH) is being applied widely as a convenient test of nitric oxide bioavailability. However, evidence linking digital PVA-RH to nitric oxide is currently lacking. Accordingly, we investigated whether nitric oxide is responsible for the increase in digital PVA. During reactive hyperemia, we used a peripheral arterial tonometer to record digital PVA at baseline and during reactive hyperemia. The role of nitric oxide in these responses was investigated in 19 healthy subjects by inhibiting nitric oxide synthesis with N(G)-nitro-L-arginine methyl ester (L-NAME). Ten subjects underwent the identical protocol with saline and five with phenylephrine, a nonspecific vasoconstrictor, instead of L-NAME. The change in digital PVA after drug administration was compared between the three groups. Relative to the response with saline (-5 +/- 2%), baseline PVA was unchanged by L-NAME infusion (-10 +/- 2%), but it decreased significantly with phenylephrine (-50 +/- 12%; P = 0.003). PVA-RH increased slightly with saline infusion (9 +/- 4%). In comparison, PVA-RH was significantly blunted by L-NAME administration (-46 +/- 21%; P = 0.002) and was relatively unchanged by phenylephrine (20 +/- 9%). The present study establishes a central role for nitric oxide in the augmentation of PVA during reactive hyperemia. The measurement of digital PVA-RH may indeed provide a simple means of assessing endothelial function in humans.

Nifedipine therapy for preterm labor: effects on placental, fetal cerebral and atrioventricular Doppler parameters in the first 48 hours

OBJECTIVE

To assess the effect of nifedipine tocolysis on Doppler parameters of the uterine, umbilical and fetal middle cerebral arteries and atrioventricular valves in the first 48 h of therapy.

METHODS

Doppler waveforms of uterine, umbilical and middle cerebral arteries and both atrioventricular valves were measured from 28 pregnant women and fetuses prior to and during nifedipine therapy for preterm labor. Maternal and fetal heart rates (FHR), maternal systolic and diastolic blood pressure, and the Doppler pulsatility index (PI) of the uterine, umbilical and middle cerebral arteries were measured. The cerebroplacental ratio (middle cerebral artery PI/umbilical artery PI) was calculated. The total time velocity integrals (TVIs) of tricuspid and mitral valves and their E- and A-wave peak velocity ratio (E/A) were measured. Friedman repeated-measures analysis of variance was used to compare the variables before and after nifedipine therapy. If significant differences were found, Wilcoxon's signed ranks test was used to analyze the difference between the two variables. A P-value of < 0.05 was considered significant.

RESULTS

Nifedipine maintenance was associated with a significant decline in maternal systolic and diastolic blood pressure after 24 h, while maternal heart rate and FHR were unaffected. The uterine artery PI had decreased significantly at 24 and 48 h, while the umbilical artery PI did not change significantly. The middle cerebral artery PI had decreased significantly at 24 and again at 48 h. A significant fall in the cerebroplacental Doppler ratio was maintained beyond 24 h. The mean E/A values, TVIs and TVI x FHR values at 24 and 48 h were unchanged from the baseline values.

CONCLUSIONS

Nifedipine maintenance tocolysis is associated with a significant decline in uterine artery and middle cerebral artery Doppler indices 24 h after the first dose. Fetal cardiac diastolic function is unaffected and the significant redistribution observed after 24 h is likely to be attributable to altered cerebral blood flow.

Pulsatile flow: a critical modulator of the natural history of atherosclerosis

Atherosclerosis is a systemic process with multi-focal distribution which progresses or regresses in an entirely independent manner within each patient. The low and oscillatory shear stress along with the geometrical particularities of the coronaries modulate an atherogenic microenvironment in susceptible to atherosclerosis regions and determine the disease's rate of progression. However, the atherogenic effect of flow pulsation remains ambiguous. Since the pulsatile nature of the blood constitutes the major generator of the oscillatory shear stress, one could hypothesize that this physiological process might exert a synergistic effect to low SS by facilitating the lesion progression. The heart rate determines directly the frequency of flow pulsation; therefore, its reduction could potentially decelerate the progression of atherosclerosis by alleviating the local atherogenic hemodynamic environment. This perspective might constitute an insight into the beneficial role of heart rate lowering agents with most significant representative the beta-blockers, which have been proved quite efficient anti-atherosclerotic drugs.

The effect of the levonorgestrel intrauterine system on uterine artery blood flow 1 year after insertion

OBJECTIVE

To assess whether the morphological alterations of the endometrium induced by the levonorgestrel intrauterine system affect the uterine artery vasculature.

METHODS

Forty-eight premenopausal women attending our gynecology clinic because of menorrhagia were enrolled into the study. Clinical measures of menstrual bleeding, endometrial thickness and Doppler flow of the uterine artery (resistance (RI) and pulsatility (PI) indices) were evaluated before and 1 year after insertion of the levonorgestrel intrauterine system. Thirty-three (69%) women were available for re-evaluation at the end of the first year and the continuation rate was 76% (n = 25). A paired samples t-test and the Mann-Whitney U-test were used for comparison of values between groups.

RESULTS

The mean age of the thirty-three patients was 44.3 +/- 7.6 years. Nine patients (27.3%) were amenorrheic and three patients were in menopause at the end of the year. After excluding the women in menopause, the increase in mean RI 1 year after insertion was statistically significant (0.86 +/- 0.07 vs. 0.81 +/- 0.08; P = 0.046), as was the decrease in uterine volume (736.9 +/- 276.9 mL vs. 972.75 +/- 465.71 mL; P = 0.029). The mean endometrial thickness decreased 1 year after insertion, but not significantly (4.6 +/- 1.6 mm vs. 6.6 +/- 3.5 mm; P = 0.07) and there was no statistically significant difference in mean PI between the groups (2.00 +/- 0.63 and 2.03 +/- 0.64 pre- and post-insertion, respectively; P = 0.83).

CONCLUSION

The increase in mean RI of the uterine artery and the decrease in uterine volume 1 year after insertion of the levonorgestrel intrauterine system may be related to its progestational effect. This increase in RI may have a role in cessation of menstruation.

Atenolol and eprosartan: differential effects on central blood pressure and aortic pulse wave velocity

BACKGROUND

Recent data suggest that atenolol may be inferior to other antihypertensive drugs in reducing cardiovascular risk in older individuals with hypertension, despite lowering peripheral blood pressure (BP). We hypothesized that that atenolol fails to reduce central BP as much as other agents. The aim of the present study was to compare the hemodynamic effects of atenolol and eprosartan in a double-blind, randomized, cross-over study.

METHODS

After a 2-week placebo run-in, 21 subjects with never-treated hypertension underwent 6 weeks of therapy with atenolol (50 mg) and eprosartan (600 mg). Central BP and augmentation index were assessed using pulse wave analysis, and aortic pulse wave velocity was measured, at baseline and at the end of each treatment.

RESULTS

Both drugs reduced peripheral BP to the same degree. However, there was a significantly greater reduction in central systolic BP with eprosartan (means +/- SEM: 16 +/- 3 v 11 +/- 2 mm Hg; P = .03). Despite identical reductions in mean pressure, atenolol reduced aortic pulse wave velocity more than eprosartan (0.8 +/- 0.1 v 0.5 +/- 0.1 m/sec; P = .005). Conversely, augmentation index and N-terminal pro-brain natiuretic peptide levels were reduced significantly after eprosartan (6% +/- 2% and 11 +/- 5 pg/mL, respectively) but were increased after atenolol (7% +/- 2% and 67 +/- 24 pg/mL, respectively).

CONCLUSIONS

These data indicate that despite similar effects on peripheral BP and a greater effect on aortic stiffness, atenolol had less impact on central systolic BP than eprosartan because it failed to reduce wave reflection. This provides one potential explanation for the failure of atenolol to improve outcome in older patients with essential hypertension.

The effect of raloxifene and tibolone on the uterine blood flow and endometrial thickness: A transvaginal Doppler study

OBJECTIVES

To evaluate and compare the effect of different than classical hormone therapy medications, such as raloxifene and tibolone, on the uterine arteries and endometrium of postmenopausal women using transvaginal ultrasonography.

METHODS

The prospective study included 62 healthy, postmenopausal women recruited from the Menopausal Clinic of the 2nd Department of Obstetrics and Gynecology of the University of Athens. Subjects were randomly allocated to receive raloxifene HCl in a daily dose of 60 mg orally (Group A-31 women) or tibolone in a daily dose of 2.5 mg orally (Group B-31 women). The study period was 6 months and all subjects were assessed using transvaginal ultrasonography before treatment initiation as well as after 3 and 6 months for evaluation of the endometrial thickness and the pulsatility (PI) and resistance (RI) indices at the level of the uterine arteries.

RESULTS

No significant differences in RI, PI and endometrial thickness were observed in the raloxifene group during the 6-month treatment. In the tibolone group, PI and RI values decreased linearly from baseline to the end of the study, whereas the endometrial thickness was significantly increased during the first 3 months remaining unaltered thereafter. Comparisons between the two study groups revealed significant percent change of values in the pre-treatment to month-3 period and no difference with regard to pre-treatment, month-3 and month-6 absolute values.

CONCLUSION

Raloxifene and tibolone exert dissimilar effects on uterine blood supply parameters and endometrial thickness.

Insulin resistance, arterial stiffness and wave reflection

Insulin resistance is associated with increased cardiovascular morbidity and mortality but the underlying mechanism(s) are incompletely understood. Epidemiological data suggest that insulin resistance and arterial stiffness are interrelated. In insulin sensitive-subjects, insulin acutely decreases the augmentation index as measured using pulse wave analysis. In insulin-resistant subjects, this effect of insulin is blunted implying that insulin resistance involves also large arteries. This may provide one mechanism linking insulin resistance and cardiovascular disease.

Protein kinase C isoform specificity of cholinergic potentiation of glucose-induced pulsatile 5-HT/ insulin release from mouse pancreatic islets

Thymeleatoxin (TMX), an activator of Ca2+-sensitive protein kinase C (cPKC) isoforms, was used to assess the PKC isoform specificity of cholinergic potentiation of glucose (11 mM)-induced pulsatile 5-HT/insulin release (PIR) from single mouse pancreatic islets. TMX (100 nM) and carbachol (Cch, 50 microM) enhanced PIR approximately 3-fold while reducing the underlying [Ca2+]i oscillations (duration and amplitude) by approximately 40-50%. Both effects were ablated by the specific PKC inhibitor bisindolylmaleimide and chronic TMX pretreatment. Cch also evoked an initial transient [Ca2+]i rise and surge of 5-HT release, which remained unaffected by chronic TMX pretreatment. It is concluded that the immediate cholinergic responses are insensitive to cPKC. In contrast, specific activation of a cPKC isoform mediates sustained cholinergic potentiation of glucose-induced insulin secretion.

Pulsatile hemodynamic effects of candesartan in patients with chronic heart failure: the CHARM Program

BACKGROUND

Abnormal large artery function and increased pulsatile load are exacerbated by excess angiotensin-II acting through the AT1 receptor and contribute to the pathogenesis and progression of chronic heart failure (CHF).

AIMS

To evaluate effects of the AT1 receptor blocker candesartan (N = 30) or placebo (N = 34) on pulsatile hemodynamics in participants with CHF in the CHARM program.

METHODS AND RESULTS

Noninvasive hemodynamics were assessed following 6 and 14 months of treatment and averaged. Using calibrated tonometry and aortic outflow Doppler, characteristic impedance was calculated as the ratio of the change in carotid pressure and aortic flow in early systole. Total arterial compliance was calculated by the diastolic area method. Brachial blood pressure, cardiac output and peripheral resistance did not differ between groups. Lower central pulse pressure in the candesartan group (57+/-20 vs. 67+/-17 mmHg, P = 0.043) was accompanied by lower characteristic impedance (200+/-78 vs. 240+/-74 dyne s/cm5, P = 0.039) and higher total arterial compliance (1.87+/-0.70 vs. 1.47+/-0.48 ml/mmHg, P = 0.008). Similar favorable differences were seen when analyses were stratified for ejection fraction (< or = 0.40 vs. >0.40) and baseline angiotensin converting enzyme inhibitor use.

CONCLUSIONS

Candesartan has a favorable effect on large artery function in patients with chronic heart failure.

[Effects of beta-blockers on transmitral, pulmonary venous flows, and spontaneous echo-contrast grades in heart failure]

OBJECTIVE

In this study, we aimed to investigate effects of metoprolol treatment on transmitral, pulmonary venous flows and spontaneous echo contrast in patients with heart failure.

METHODS

Twenty-four patients (mean age: 55+/-8 years) with heart failure were enrolled to the study. All were given metoprolol succinate with titrated target dose of 50 mg/d controlled release tablets for 1 month. Transmitral flow and pulmonary venous flow, systolic, diastolic and atrial reversal flow velocities were measured, and compared with the pretreatment values.

RESULTS

Heart rate significantly decreased. No significant change was observed in ejection fraction. When the post treatment values were compared with the pretreatment values, it was detected that isovolumetric relaxation time significantly decreased (p<0.05), mitral E wave and E/A ratio were significantly increased (p<0.05 and p<0.05, respectively) after the treatment. A significant increase was observed in pulmonary vein systolic velocity after metoprolol treatment (p<0.05).

CONCLUSION

Metoprolol treatment can cause an improvement in transmitral and pulmonary venous flows.

Pulsatile ocular blood flow change after treatment with systemic steroid in patients with Graves' ophthalmopathy

PURPOSE

Our previous study has demonstrated an impairment of pulsatile ocular blood flow (POBF) in patients with Graves'ophthalmopathy (GO). Here we further evaluate the haemodynamic change in GO patients after systemic steroid.

METHODS

In a prospective, interventional, consecutive clinical case series, all patients with active and moderately severe GO who underwent systemic steroid treatment were evaluated. The change of POBF and the clinical activity and severity of the disease were assessed.

RESULTS

In total, 11 patients underwent intravenous methylprednisolone pulse therapy followed by 2-month oral prednisolone therapy. POBF improved from a mean value of 476.5 to 614.7 microl/min (P<0.001) after treatment. Likewise, the mean clinical activity score reduced from 4.8 to 1.6. However, systemic steroid had less effect on the severity of GO. It also revealed that there is a greater improvement of POBF in those with more clinical activity score (>4) at the onset.

CONCLUSIONS

Following treatment with systemic steroid we have demonstrated a significant improvement in POBF in patients with GO.